x86: move suspend wakeup code to C

Move wakeup code to .c, so that video mode setting code can be shared
between boot and wakeup. Remove nasty assembly code in 64-bit case by
re-using trampoline code. Stack setup was fixed to clear high 16bits
of %esp, maybe that fixes some machines.

.c code sharing and morse code was done H. Peter Anvin, Sam Ravnborg
reviewed kbuild related stuff, and it seems okay to him. Rafael did
some cleanups.

[rjw:
* Made the patch stop breaking compilation on x86-32
* Added arch/x86/kernel/acpi/sleep.h
* Got rid of compiler warnings in arch/x86/kernel/acpi/sleep.c
* Fixed 32-bit compilation on x86-64 systems
* Added include/asm-x86/trampoline.h and fixed the non-SMP
  compilation on 64-bit x86
* Removed arch/x86/kernel/acpi/sleep_32.c which was not used
* Fixed some breakage caused by the integration of smpboot.c done
  under us in the meantime]

Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Reviewed-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

10 files changed, 353 insertions, 0 deletions

diff --git a/arch/x86/kernel/acpi/realmode/Makefile b/arch/x86/kernel/acpi/realmode/Makefile
new file mode 100644
index 000000000000..092900854acc
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/Makefile
@@ -0,0 +1,57 @@
+#
+# arch/x86/kernel/acpi/realmode/Makefile
+#
+# This file is subject to the terms and conditions of the GNU General Public
+# License.  See the file "COPYING" in the main directory of this archive
+# for more details.
+#
+
+targets		:= wakeup.bin wakeup.elf
+
+wakeup-y	+= wakeup.o wakemain.o video-mode.o copy.o
+
+# The link order of the video-*.o modules can matter.  In particular,
+# video-vga.o *must* be listed first, followed by video-vesa.o.
+# Hardware-specific drivers should follow in the order they should be
+# probed, and video-bios.o should typically be last.
+wakeup-y	+= video-vga.o
+wakeup-y	+= video-vesa.o
+wakeup-y	+= video-bios.o
+
+targets		+= $(wakeup-y)
+
+bootsrc		:= $(src)/../../../boot
+
+# ---------------------------------------------------------------------------
+
+# How to compile the 16-bit code.  Note we always compile for -march=i386,
+# that way we can complain to the user if the CPU is insufficient.
+# Compile with _SETUP since this is similar to the boot-time setup code.
+KBUILD_CFLAGS	:= $(LINUXINCLUDE) -g -Os -D_SETUP -D_WAKEUP -D__KERNEL__ \
+		   -I$(srctree)/$(bootsrc) \
+		   $(cflags-y) \
+		   -Wall -Wstrict-prototypes \
+		   -march=i386 -mregparm=3 \
+		   -include $(srctree)/$(bootsrc)/code16gcc.h \
+		   -fno-strict-aliasing -fomit-frame-pointer \
+		   $(call cc-option, -ffreestanding) \
+		   $(call cc-option, -fno-toplevel-reorder,\
+			$(call cc-option, -fno-unit-at-a-time)) \
+		   $(call cc-option, -fno-stack-protector) \
+		   $(call cc-option, -mpreferred-stack-boundary=2)
+KBUILD_CFLAGS	+= $(call cc-option, -m32)
+KBUILD_AFLAGS	:= $(KBUILD_CFLAGS) -D__ASSEMBLY__
+
+WAKEUP_OBJS = $(addprefix $(obj)/,$(wakeup-y))
+
+LDFLAGS_wakeup.elf	:= -T
+
+CPPFLAGS_wakeup.lds += -P -C
+
+$(obj)/wakeup.elf: $(src)/wakeup.lds $(WAKEUP_OBJS) FORCE
+	$(call if_changed,ld)
+
+OBJCOPYFLAGS_wakeup.bin	:= -O binary
+
+$(obj)/wakeup.bin: $(obj)/wakeup.elf FORCE
+	$(call if_changed,objcopy)
diff --git a/arch/x86/kernel/acpi/realmode/copy.S b/arch/x86/kernel/acpi/realmode/copy.S
new file mode 100644
index 000000000000..dc59ebee69d8
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/copy.S
@@ -0,0 +1 @@
+#include "../../../boot/copy.S"
diff --git a/arch/x86/kernel/acpi/realmode/video-bios.c b/arch/x86/kernel/acpi/realmode/video-bios.c
new file mode 100644
index 000000000000..7deabc144a27
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/video-bios.c
@@ -0,0 +1 @@
+#include "../../../boot/video-bios.c"
diff --git a/arch/x86/kernel/acpi/realmode/video-mode.c b/arch/x86/kernel/acpi/realmode/video-mode.c
new file mode 100644
index 000000000000..328ad209f113
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/video-mode.c
@@ -0,0 +1 @@
+#include "../../../boot/video-mode.c"
diff --git a/arch/x86/kernel/acpi/realmode/video-vesa.c b/arch/x86/kernel/acpi/realmode/video-vesa.c
new file mode 100644
index 000000000000..9dbb9672226a
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/video-vesa.c
@@ -0,0 +1 @@
+#include "../../../boot/video-vesa.c"
diff --git a/arch/x86/kernel/acpi/realmode/video-vga.c b/arch/x86/kernel/acpi/realmode/video-vga.c
new file mode 100644
index 000000000000..bcc81255f374
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/video-vga.c
@@ -0,0 +1 @@
+#include "../../../boot/video-vga.c"
diff --git a/arch/x86/kernel/acpi/realmode/wakemain.c b/arch/x86/kernel/acpi/realmode/wakemain.c
new file mode 100644
index 000000000000..883962d9eef2
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/wakemain.c
@@ -0,0 +1,81 @@
+#include "wakeup.h"
+#include "boot.h"
+
+static void udelay(int loops)
+{
+	while (loops--)
+		io_delay();	/* Approximately 1 us */
+}
+
+static void beep(unsigned int hz)
+{
+	u8 enable;
+
+	if (!hz) {
+		enable = 0x00;		/* Turn off speaker */
+	} else {
+		u16 div = 1193181/hz;
+
+		outb(0xb6, 0x43);	/* Ctr 2, squarewave, load, binary */
+		io_delay();
+		outb(div, 0x42);	/* LSB of counter */
+		io_delay();
+		outb(div >> 8, 0x42);	/* MSB of counter */
+		io_delay();
+
+		enable = 0x03;		/* Turn on speaker */
+	}
+	inb(0x61);		/* Dummy read of System Control Port B */
+	io_delay();
+	outb(enable, 0x61);	/* Enable timer 2 output to speaker */
+	io_delay();
+}
+
+#define DOT_HZ		880
+#define DASH_HZ		587
+#define US_PER_DOT	125000
+
+/* Okay, this is totally silly, but it's kind of fun. */
+static void send_morse(const char *pattern)
+{
+	char s;
+
+	while ((s = *pattern++)) {
+		switch (s) {
+		case '.':
+			beep(DOT_HZ);
+			udelay(US_PER_DOT);
+			beep(0);
+			udelay(US_PER_DOT);
+			break;
+		case '-':
+			beep(DASH_HZ);
+			udelay(US_PER_DOT * 3);
+			beep(0);
+			udelay(US_PER_DOT);
+			break;
+		default:	/* Assume it's a space */
+			udelay(US_PER_DOT * 3);
+			break;
+		}
+	}
+}
+
+void main(void)
+{
+	/* Kill machine if structures are wrong */
+	if (wakeup_header.real_magic != 0x12345678)
+		while (1);
+
+	if (wakeup_header.realmode_flags & 4)
+		send_morse("...-");
+
+	if (wakeup_header.realmode_flags & 1)
+		asm volatile("lcallw   $0xc000,$3");
+
+	if (wakeup_header.realmode_flags & 2) {
+		/* Need to call BIOS */
+		probe_cards(0);
+		set_mode(wakeup_header.video_mode);
+	}
+}
diff --git a/arch/x86/kernel/acpi/realmode/wakeup.S b/arch/x86/kernel/acpi/realmode/wakeup.S
new file mode 100644
index 000000000000..f9b77fb37e5b
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/wakeup.S
@@ -0,0 +1,113 @@
+/*
+ * ACPI wakeup real mode startup stub
+ */
+#include <asm/segment.h>
+#include <asm/msr-index.h>
+#include <asm/page.h>
+#include <asm/pgtable.h>
+
+	.code16
+	.section ".header", "a"
+
+/* This should match the structure in wakeup.h */
+		.globl	wakeup_header
+wakeup_header:
+video_mode:	.short	0	/* Video mode number */
+pmode_return:	.byte	0x66, 0xea	/* ljmpl */
+		.long	0	/* offset goes here */
+		.short	__KERNEL_CS
+pmode_cr0:	.long	0	/* Saved %cr0 */
+pmode_cr3:	.long	0	/* Saved %cr3 */
+pmode_cr4:	.long	0	/* Saved %cr4 */
+pmode_efer:	.quad	0	/* Saved EFER */
+pmode_gdt:	.quad	0
+realmode_flags:	.long	0
+real_magic:	.long	0
+trampoline_segment:	.word 0
+signature:	.long	0x51ee1111
+
+	.text
+	.globl	_start
+	.code16
+wakeup_code:
+_start:
+	cli
+	cld
+
+	/* Set up segments */
+	movw	%cs, %ax
+	movw	%ax, %ds
+	movw	%ax, %es
+	movw	%ax, %ss
+
+	movl	$wakeup_stack_end, %esp
+
+	/* Clear the EFLAGS */
+	pushl	$0
+	popfl
+
+	/* Check header signature... */
+	movl	signature, %eax
+	cmpl	$0x51ee1111, %eax
+	jne	bogus_real_magic
+
+	/* Check we really have everything... */
+	movl	end_signature, %eax
+	cmpl	$0x65a22c82, %eax
+	jne	bogus_real_magic
+
+	/* Call the C code */
+	calll	main
+
+	/* Do any other stuff... */
+
+#ifndef CONFIG_64BIT
+	/* This could also be done in C code... */
+	movl	pmode_cr3, %eax
+	movl	%eax, %cr3
+
+	movl	pmode_cr4, %ecx
+	jecxz	1f
+	movl	%ecx, %cr4
+1:
+	movl	pmode_efer, %eax
+	movl	pmode_efer + 4, %edx
+	movl	%eax, %ecx
+	orl	%edx, %ecx
+	jz	1f
+	movl	$0xc0000080, %ecx
+	wrmsr
+1:
+
+	lgdtl	pmode_gdt
+
+	/* This really couldn't... */
+	movl	pmode_cr0, %eax
+	movl	%eax, %cr0
+	jmp	pmode_return
+#else
+	pushw	$0
+	pushw	trampoline_segment
+	pushw	$0
+	lret
+#endif
+
+bogus_real_magic:
+1:
+	hlt
+	jmp	1b
+
+	.data
+	.balign	4
+	.globl	HEAP, heap_end
+HEAP:
+	.long	wakeup_heap
+heap_end:
+	.long	wakeup_stack
+
+	.bss
+wakeup_heap:
+	.space	2048
+wakeup_stack:
+	.space	2048
+wakeup_stack_end:
diff --git a/arch/x86/kernel/acpi/realmode/wakeup.h b/arch/x86/kernel/acpi/realmode/wakeup.h
new file mode 100644
index 000000000000..ef8166fe8020
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/wakeup.h
@@ -0,0 +1,36 @@
+/*
+ * Definitions for the wakeup data structure at the head of the
+ * wakeup code.
+ */
+
+#ifndef ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H
+#define ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H
+
+#ifndef __ASSEMBLY__
+#include <linux/types.h>
+
+/* This must match data at wakeup.S */
+struct wakeup_header {
+	u16 video_mode;		/* Video mode number */
+	u16 _jmp1;		/* ljmpl opcode, 32-bit only */
+	u32 pmode_entry;	/* Protected mode resume point, 32-bit only */
+	u16 _jmp2;		/* CS value, 32-bit only */
+	u32 pmode_cr0;		/* Protected mode cr0 */
+	u32 pmode_cr3;		/* Protected mode cr3 */
+	u32 pmode_cr4;		/* Protected mode cr4 */
+	u32 pmode_efer_low;	/* Protected mode EFER */
+	u32 pmode_efer_high;
+	u64 pmode_gdt;
+	u32 realmode_flags;
+	u32 real_magic;
+	u16 trampoline_segment;	/* segment with trampoline code, 64-bit only */
+	u32 signature;		/* To check we have correct structure */
+} __attribute__((__packed__));
+
+extern struct wakeup_header wakeup_header;
+#endif
+
+#define HEADER_OFFSET 0x3f00
+#define WAKEUP_SIZE   0x4000
+
+#endif /* ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H */
diff --git a/arch/x86/kernel/acpi/realmode/wakeup.lds.S b/arch/x86/kernel/acpi/realmode/wakeup.lds.S
new file mode 100644
index 000000000000..22fab6c4be15
--- /dev/null
+++ b/arch/x86/kernel/acpi/realmode/wakeup.lds.S
@@ -0,0 +1,61 @@
+/*
+ * wakeup.ld
+ *
+ * Linker script for the real-mode wakeup code
+ */
+#undef i386
+#include "wakeup.h"
+
+OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386")
+OUTPUT_ARCH(i386)
+ENTRY(_start)
+
+SECTIONS
+{
+	. = HEADER_OFFSET;
+	.header : {
+		 *(.header)
+	}
+
+	. = 0;
+	.text : {
+		 *(.text*)
+	}
+
+	. = ALIGN(16);
+	.rodata : {
+		*(.rodata*)
+	}
+
+	.videocards : {
+		video_cards = .;
+		*(.videocards)
+		video_cards_end = .;
+	}
+
+	. = ALIGN(16);
+	.data : {
+		 *(.data*)
+	}
+
+	.signature : {
+		end_signature = .;
+		LONG(0x65a22c82)
+	}
+
+	. = ALIGN(16);
+	.bss :	{
+		__bss_start = .;
+		*(.bss)
+		__bss_end = .;
+	}
+
+	. = ALIGN(16);
+	_end = .;
+
+	/DISCARD/ : {
+		*(.note*)
+	}
+
+	. = ASSERT(_end <= WAKEUP_SIZE, "Wakeup too big!");
+}